The purpose of this unique experiment is to determine if earthworms respond to different light waves.
Things Required:
Earthworms (purchase at a bait shop)
2 torches
Red cellophane
2 shoeboxes with lids
Tape
Scissors
Paper towels
Notebook paper
Directions:
Prepare both shoeboxes by putting a circular hole in one end of each lid. The hole should be smaller than the end of the torch. Tape notebook paper to the lids of each box so that it may hang about one inch (21/2 cm) from the floor of the shoeboxes, and about four inches (10 cm) from the end opposite the hole in the lid (see diagram). Place moistened paper towels in the bottom of each box.
Position five earthworms in each box under where the hole in the lid will be. Place a torch over one of the holes, and turn it on. Cover the second hole with four layers of red cellophane. Position the torch over the hole and turn it on. Leave both boxes undisturbed for 30 minutes. Remove the torches and open the lids.
Observe the position of the worms.
This Is What Happens:
The worms have crawled away from the white light and are under the paper partition where it is darker. The worms under the red light have made little or no change in their position.
Science Behind It:
An earthworm has a nervous system with a simple brain. There are no obvious sense organs such as eyes or ears, but the worms respond to stimuli such as white light. The worms do not respond to red lightwaves. This fact helps fishermen while searching for worms at night. Earthworms often surface at night and, therefore, are referred to as night crawlers.
